This is great. It's a site that uses the international Automatic Identification System broadcasts from shipping to plot all the ships off Liverpool, as far up as Belfast and Stranraer, as far over as Dublin, and even in the Manchester Ship Canal, on a map. Better yet, there's even a mashup version using Google Maps, here (beware, there is a slow running script in the page that handles the periodic refresh, which is why I resisted the temptation to spooge the Gmap into this post).
Unfortunately, the bastards are after it. The International Maritime Organisation apparently is concerned that putting this data on a web site might be a threat to security - hey, the terrorists might see, or the pirates. This is profoundly stupid. AIS works like this: each ship broadcasts a chunk of information every so often on an open VHF channel, in the clear. That includes the ship's name, destination, course, speed, position, type, and a unique identifier. And that's it. Anyone with a radio and trivially available equipment can plot ships...after all, it's quite a bit easier to buy the kit, designed for use at sea, for a couple of hundred quid than try to get an Internet connection into your wildly bucking pirate RIB racing over the Strait of Malacca.
In fact, this openness is a feature, not a bug. The point should be that anyone, however poor and backward, can tell where ships are off their coast, or keep from running into them.